1. Field:
This invention is in the field of sampling molten materials.
2. State of the Art:
In many smelting processes it is desirable to sample a slag or matte as it flows in molten condition from a tap hole or down a launder and to subject the samples to various tests. The results of the tests are used to help control the effectiveness of the process. For example, in the smelting of copper, it is desirable to monitor the composition of the slag flowing from the furnace to ensure that the desired chemical reactions have taken place and enough time has been allowed for the slag and matte phases in the furnace to separate satisfactorily. Too much copper sulfide in the slag is an indication of incomplete separation.
The common practice is to manually take a sample from the stream of molten material with a large spoon designed for the purpose. It is important in taking such a sample to cut across the entire cross-section of the stream, but present sampling methods have proven deficient in this respect. Many times the sample will be taken from the most accessible area, which is usually the top of the flowing stream. Even when the complete stream is cut by the spoon, the material caught at the bottom is usually forced out and displaced by material in the upper portion as the spoon is drawn through the stream. A uniform sample is not normally obtained by this method of sampling.